The ability to control the opening of a door can be highly desirable. For instance, the ability to prevent an emergency exit door of a public building (such as a shop) from being readily opened can be desirable for security reasons. While there exists many door locking mechanisms that could be used to control the opening of the door, existing door locking mechanisms can be unsuitable in some situations because they do not meet building safety requirements. More specifically, existing door locking mechanisms will commonly only release the door for opening if the appropriate key is used to unlock the mechanism. In this regard, some building safety standards require door locking mechanisms to release the door without a key so that it can be opened relatively easily.